Primary Care Otolaryngology

Chapter 5

The treatment for cholesteatoma is surgical removal. While excision gets rid of the cholesteatoma, the underlying eustachian tube dysfunction is still present. Thus, cholesteatoma has the propensity to recur. Once patients have undergone surgery for removal of a cholesteatoma, they will need continuous monitoring of their ears for the rest of their lives. Another way cholesteatoma can develop is when squamous epithelium migrates into the middle ear space through a hole in the eardrum. The perforation can come from a previous otitis media infection, a PE tube hole that did not heal, or trauma. Marginal perforations, or holes along the outer portion of the eardrum, are more likely to allow migration of epithelium than central perforations . Remember that the eardrum has three layers: cuboidal epithelium in the middle ear, a fibrous layer in the middle, and squamous epithelium on the outside. When there is a perforation, all three layers start to proliferate , but if the squamous layer and the cuboidal layer meet , the fibrous layer will stop . This can lead to a chronic perforation in which the middle ear is constantly being exposed to the outside, and thus develops a low-grade inflammation. Clinical Example A 14-year-old boy comes to your office complaining of painless right ear drainage. He is otherwise healthy, although he did have PE tubes in his ears as a child. On examination, you find he has slightly turbid drainage coming from a hole in his right eardrum. You diagnose chronic otitis media and learn that he does not know he has a perforation. He has not been trying to keep water out of his ear. You assume he has a Pseudo- monas aeruginosa infection and prescribe ofloxacin otic solution (0.3%) twice a day for 10 days. He returns in two weeks with a dry ear and a small residual eardrum perforation. You next order an audiogram , a hearing test that shows a 15-dB conductive hearing loss with normal discrimina- tion (ability to understand words). You tell the patient to keep water out of his ear. He comes back in four to six weeks and has not had any more drainage, so you refer him for a tympanoplasty . Tympanoplasty Tympanoplasty , an operation to repair a hole in the eardrum , is gener- ally performed either through the ear canal or from behind the ear . The surgeon freshens up the edges of the hole. Then, because the fibrous tissue will not grow with squamous epithelium meeting cuboidal epithelium, a piece of fascia temporalis (the fibrous connective tissue overlying the temporalis muscle) or tragal perichondrium (the lining overlying the

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Primary Care Otolaryngology